Vestil SWA Series, Instruction Manual

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7 Film Tension Adjust
The pre-stretch unit has a set pre-stretch percen tage of 240% (can not be changed) which is
called the First Stage Pre-stretch, therefore there is no pre-stretch setting device on the control panel.
The pre-stretch percentage can be slightly adju sted to a m aximum of 320%, which is called the
Second Stage Pre-stretch, and its adjusting method is shown below:
There are 2 sets of nuts and bolts located on the top and bottom of the free roller and is used to
adjust pre-stretch ratio.
Pull away the free roller and 2 springs can be seen attached to the 2 sets of nuts and bolts.
Slightly tighten the nuts onto the bolts to pull on the springs in order to increase pre-stretch ratio.
Warning:
Do not pull on free roller while pre-stretch unit in operation, as not to cause film
jamming into rollers.